The first Sun-like stars were lonely orbs moving through a universe devoid of planets or life. They were born (top), lived (middle), and died (bottom) in barren, lifeless isolation. Yet they helped to seed the universe with heavy elements like carbon and oxygen that would one day form planets like our Earth. Credit: David Aguilar, Harvard-Smithsonian Center for Astrophysics.

Supercomputer simulations by Volker Bromm and colleagues show that the first supernovae were incredibly energetic, spewing tremendous amounts of iron, carbon, oxygen, and other elements across thousands of light-years of space. These first supernovae seeded the universe with the "stuff of life." Credit: Volker Bromm (CfA), Naoki Yoshida (National Astronomical Observatory of Japan), Lars Hernquist (CfA), and Christine Pulliam (CfA).

In the early universe, small protogalaxies clustered together into vast filamentary structures. Within these glowing galactic building blocks, supernovae exploded like firecrackers as the first, "greatest generation" of stars rapidly used up their fuel and died. Credit: Christine Pulliam (CfA), Volker Springel (Max Planck Institute for Astrophysics), and Lars Hernquist (CfA).